off-side rule

A lexical convention due to Landin, allowing the scope of

declarations in a program to be expressed by indentation. Any

non-whitespace token to the left of the first such token on

the previous line is taken to be the start of a new

declaration. Used in, for example, Miranda and Haskell.

[P.J. Landin "The Next 700 Programming Languages", CACM vol 9

pp157-165, March 1966]